The Football Association and Football Supporters' Association are investigating after England fans complained of facing heavy-handed policing and tear gas before the Nations League match in Greece.
Lee Carsley's side was backed by 3,500 travelling supporters in Thursday's encounter at the sold-out Olympic Stadium in Athens.
England secured a 3-0 victory against Greece on an evening that started with some fans facing problems on their way into the ground.
An FA spokesperson told the PA news agency: "We are aware that some of our fans had a difficult experience outside the ground and are obtaining more information on exactly what happened."
The FSA's Free Lions Fans' Embassy posted on X: "Unfortunately, once again, we are having to ask England supporters to send in their witness accounts to ourselves regarding the situation outside of the Athens Olympic Stadium.
"Despite being told how things would operate in advance, to see the exact opposite occur in some cases, and to see the treatment of our fans by local police using shields and tear gas to do something as simple as rearrange a queue, is so incredibly frustrating.
"We'll say more over the next 24 hours, but in the meantime, if fans can email info@thefsa.org.uk with your experiences, we will work with the FA and we will raise with Fans Europe and in turn UEFA, who have already been made aware.
"On a night where we had a great result on the pitch, there is still clearly so much needed to do off it to ensure our supporters aren't put in unjustifiably dangerous situations."
England fans complained of being "pushed" and receiving "heavy handed" treatment from Greek police outside the Olympic Stadium.
Jack Loftus, from Telford, told PA: "It's been mental. They went to adjust the queue at the front to make it narrower and longer and just did it with force. They were pushing the crowd amongst the fence.
"They ultimately treat us like animals, then they'll act the victim if there's retaliation. Sick of the foreign police."
Jamie Murray from Bury complained of "heavy handed" treatment.
"England fans were just queuing to get in. 3,500 through one gate, it hadn't really been thought out," Mr Murray told PA.
European football's governing body UEFA is awaiting reports from its match delegate before deciding on any next steps.
